I'll be the voice of dissent. We upgraded to the DxDP on our last trip (with a 6yo and a 10 mo old) and were glad we did. We ate at a character meal just about every day, including Cinderella's Royal Table. We also enjoyed the Hoop Dee Doo Revue (2 credits). We probably wouldn't have done these things if we were paying for them OOP, as the individual decisions to part with extra $$ would have been harder than the one choice to just upgrade our dining overall, if that makes any sense.
To offset the cost of our deluxe dining plan, we downgraded our resort from a moderate to a value. In hindsight I should have added a rental car, though, because Disney transport made it difficult to travel to other resorts for a TS breakfast, and we didn't enjoy the food court experience at all, especially in the morning when it was total chaos.
We traveled during a very low season when there were very few lines to wait in, so we didn't regret missing time in the parks during meals.
One consideration, though, in the budget is the additional gratuities for all those TS meals.